title: Extraction of diquat with 1-butanol from biological materials.
abstract: Diquat can be extracted with 1-butanol from high pH solution in the presence of several moderate reductants. The red colored reduced compound of diquat in water turns to a purple compound in 1-butanol. The absorption of the purple compound is 0.105 at 383 nm and 0.119 at 520 nm in 1 microgram diquat/ml 1-butanol. The latter value is a little higher than that of the red compound at 495 nm in water. The purple compound is much more stable than the red compound in water. More than 80% of 10 ppm diquat added can be extracted from serum, blood, tissues, urine and some drinks. The extraction with 1-butanol is useful for concentration of diquat contained in large volume. The lower limit of detection is 0.1 microgram/ml 1-butanol. Paraquat is insoluble in 1-butanol under the same condition. Therefore, this method is applicable for the determination of diquat when paraquat is also contained in the solution.
authors.affiliation: Department of Legal Medicine, Hamamatsu University, School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Minakata
authors.forename: O
authors.initials: O
authors.lastname: Suzuki
authors.forename: M
authors.initials: M
authors.lastname: Asano
mesh_terms: D020001:1-Butanol; D001628:Beverages; D000440:Butanols; D004178:Diquat / Q000097:blood / Q000302:isolation & purification* / Q000652:urine; D005504:Food Analysis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008623:Mercaptoethanol; D011726:Pyridinium Compounds / Q000302:isolation & purification*
chemical_list: D000440:Butanols; D011726:Pyridinium Compounds; D008623:Mercaptoethanol; D020001:1-Butanol; D004178:Diquat